Manufacturing process of shoe with internally waterproofed fabric upper

ABSTRACT

A manufacturing process is provided for a shoe with a fabric upper that is internally provided with a waterproof coating layer made of plastic material. The process includes the step of piercing of the upper in order to inject plastic material in an intermediate space between a core of a mold and the upper.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT

Not applicable.

INCORPORATION-BY-REFERENCE OF MATERIALS SUBMITTED ON A COMPACT DISC

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present patent application for industrial invention relates to amanufacturing process of a shoe provided with an internally waterproofedfabric upper, and a molding assembly to perform the manufacturingprocess.

Also if following the description specifically refers to boots, thescope of the invention extends to any type of shoe provided with closedor opened upper, such as Ballet flats or Dolly shoes, sandals, sabots,and like.

2. Description of Related Art Including Information Disclosed Under 37CFR 1.97 and 37 CFR 1.98.

Known are boots composed of a rubber sole and a fabric upper fixed tothe sole. In particular, the upper is provided with a structure that issimilar to a sock. The upper is formed of a tubular section adapted toembrace the user's leg and of a base sack adapted to receive the footand surround it completely. The bottom of the base sack must be exactlydisposed in contact with the upper side of the sole. Generally fabricuppers are used, since this type of material can have any desired colorand/or surface decoration, thus guaranteeing the aesthetic peculiarityof the boot provided with such an upper.

Nevertheless, a fabric upper is not intrinsically able to offer theself-support, resistance and waterproof properties that are compatiblewith the use of a boot, i.e. a type of footwear that is typically usedin cold months with adverse weather conditions. For this reason, thefabric of such an upper is coated by applying an external layer oftransparent or colored plastic material (preferably PVC) that, inaddition to increasing the resistance and self-support properties of theupper, allows leaving the color and decoration of the fabric used tomake the upper.

Such an operation is made with a special mold, which is normally formedof three cooperating parts.

The first part consists of a core that reproduces the user's leg andfoot. The fabric upper to be coated with the plastic material isinserted on said core.

The second part consists of a mold die, which is preferably formed oftwo semi-shells, adapted to be tightened on the two sides of the core,which is already provided with the fabric upper.

The third part consists in a mold lid adapted to close the die, incontact with the bottom of the core and substantially with the bottom ofthe “sack” of the upper inserted on the core.

Transparent plastic material in fluid state is injected into the mold.In particular, such an injection is made by means of nozzles insertedthrough said lid. The plastic material injected by the nozzlespenetrates between the fabric upper and the walls of the mold coveringthe entire surface of the upper.

After completing this step of the injection process, the lid is removedand replaced with a second lid, which is specifically adapted to moldthe rubber sole directly under the bottom of the fabric upper, which iscompletely coated with the plastic material.

Such a technology is highly impaired by a significant drawback. Thelayer of transparent plastic material that consolidates externally onthe fabric upper prevents the user from feeling the fabric and partiallyalters the visual perception of the color and/or decoration of the samefabric.

The impression generated by a boot manufactured according to thetraditional technology is that the upper is directly made of a coloredand/or decorated material, and not of fabric.

The purpose of the present invention is to provide a shoe with fabricupper that is waterproof and in the same time it is perceived as fabricboth from the tactile and the visual viewpoint.

BRIEF SUMMARY OF THE INVENTION

The inventive idea that has allowed for achievement of such a purposeconsists in applying the plastic coating layer on the inside, and not onthe outside, of the upper, as in the prior art shoes.

In view of the above, although both the fabric upper and the boot arewaterproof, the fabric of the upper is perceived as such on the outsideof the shoe. So, the user can feel the fabric and the color and/ordecoration of the fabric can maintain the initial characteristics.

Such an inventive solution is implemented by means of the process of theinvention, which can be implemented by using the molding installationsthat are currently used, with some minor modifications, and consequentlywith an insignificant increase of the costs for manufacturer of similarshoes provided with fabric upper.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

For explanatory reasons, the description of the invention continues withreference to the attached drawings, which only have an illustrative, notlimiting value, wherein:

FIGS. 1 to 4 are diagrammatic sectional views of the operating steps ofthe process of the invention;

FIG. 1A is an enlarged view of FIG. 1;

FIG. 5 is a partially sectional view of the boot obtained according tothe process shown in FIGS. 1 to 4;

FIGS. 6 and 7 show the operating steps of a second embodiment of theprocess of the invention;

FIG. 6A is an enlarged view of FIG. 6;

FIG. 8 is a partially sectional side view of one of the diffusersprovided in the core of the mold used for the process of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, the process of the invention provides for using amold (S) composed of three parts.

The first part includes a core (1) that reproduces the shape of theuser's leg and foot. The core (1) comprise a bottom (1 p) reproducingthe foot plantar. An upper (10) is made of fabric and is intended to befit on the exterior of the core. The upper (10) has a shapesubstantially of a sock and has a bottom (10 p) intended to bepositioned under the bottom (1 p) of the core.

The second part includes a die (2) of the mold (S), which comprises twosemi-shells. The die (2) is adapted to surround the core (1) in order togenerate a lateral gap (4) between the core (1) and the die (2).

The third part includes a lid (3) of the mold (S), which is adapted toclose the die (2) substantially at the height of the bottom (1 p) ofsaid core (1), in order to generate a lower gap (104) between the lid(3) and the bottom (1 p) of the core. The lower gap (104) communicateswith the lateral gap (4). In this manner, a gap (4, 104) is generatedbetween the core (1) and the mold (S) surrounding laterally andinferiorly the core (1). The lid (3) is provided with at least one hole(3 a) adapted to receive a nozzle (30) (FIG. 2) to inject the plasticmaterial in fluid state inside the mold (S).

The nozzle (30) comprises a pointed head (31) which enters into thelower gap (104) of the mold and the pointed head (31) pierces the bottom(10 p) of the upper in order to inject the plastic material in anintermediate space (4 a) between the core (1) and the upper (10). Inthis manner, the plastic material can cover the interior surface of theupper, i.e. the surface of the upper facing towards the core (1).

Referring to FIG. 1A, the core (1) of the mold (S) is provided with oneor more diffusers (D) suitable for coupling with the pointed head (31)of the nozzle in order to spread the plastic material at fluid state.The diffusers (D) are disposed under the bottom (1 b) of the core andover the bottom (10 p) of the upper. Each diffuser (D) is disposed in aposition that corresponds to one of the holes (3 a) of the lid (3).

Referring to FIG. 8, each diffuser (D) comprises a plate (100) having acylindrical shape. The plate (100) has a first side (100 a) abuttingagainst the surface of the core (1) of the mold and a second side (100b) opposed to the first side (100 a). The diffuser (D) comprises afixing pin (101) protruding from the first side (100 a) of the plate ofthe diffuser. The fixing pin (101) is adapted to be inserted into thecore (1).

A chamber (100 c) having a cylindrical shape is provided inside theplate (100) of the diffuser. The camber (100 c) has an opening on thesecond side (100 b) of the plate in order to receive the pointed head(31) of the nozzle. The plate (100) has lateral walls with radial slot(100 d) communicating with the camber (100 c) for a radial spreading ofthe plastic material. The radial slots (100 d) are disposes atapproximately half of the height of the chamber (100 c).

After inserting the upper (10) onto the core (1) of the mold (S), thediffusers (D) are disposed between the core (1) and the upper (10).

In order to inject the thermoplastic material in fluid state, aninjection nozzle (30) is inserted into a hole (3 a) of the lid (3), insuch manner that the pointed head (31) of the nozzle (30) can pierce theupper (10) and penetrate inside the chamber (100 c) of a diffuser (D).

Upon injection, the plastic material in fluid state is delivered inradial direction through the radial slots (100 c) of each diffuser (D),in such manner to penetrate in the intermediate space (4 a) between thesurface of the core (1) and the internal side of the upper (10) for theentire extension of the gap (4, 104) of the mold (S). Consequently, uponconsolidation, the plastic material generates a coating layer (10 a)(FIG. 2) that extends on the entire internal surface of the upper (10),both on the tubular section of the upper (10), which is adapted toreceive the user's leg, and on the base sack of the upper, which isadapted to receive the user's foot.

On the contrary, the external surface of the upper (10) is not cover ofsaid plastic material, thus maintaining the tactile and visual aspect ofa fabric material.

FIGS. 3 and 4 show the second step of the molding process of the shoeaccording to the invention, which is carried out according totraditional principles.

The first lid (3) used to inject the plastic material on the inside ofthe upper (10) is removed and replaced by a second lid (5) adapted tofavor the molding of the sole (11) under the upper (10).

The second lid (5) is provided with a cavity (5 b) that reproduces theshape of a sole (11) to be obtained and at least one hole (5 a) adaptedto receive an injection nozzle (50) of the plastic material.

In particular, FIG. 4 shows the installation of an injection nozzle (50)inside the hole (5 a) of the second lid and the consequent filling ofthe cavity (5 b) of the second lid with the molding material that isused to form the sole (11). In this case a boot (ST) is obtained (FIG.5).

As soon as the molding step of the sole (11) is completed, the entiremold (S) is opened in order to remove the boot (ST), which is nowcomplete in all its parts, from the core (1).

The boot (ST) after being removed from the mold (S), as well as thepresence of the desired plastic layer (10 a) on the inside of the entireupper (10).

The versatility and efficacy of the process according to the presentinvention are clear also from another perspective. Whereas according tothe prior art the external coating layer of plastic material isnecessarily transparent in order not to conceal the fabric of the upper,the process of the invention allows for making the internal coatinglayer with any colored plastic material, possibly matching the colorand/or decoration of the fabric used for the upper.

Likewise, in order to guarantee a higher comfort to the foot, theplastic coating layer (11) applied on the inside of the upper (10) iscoated with a fabric lining (12).

With reference to FIGS. 6 and 7, in order to obtain such an embodimentof the boot of the invention, a fabric lining (12) is provided, beingshaped as a sock that reproduces both the user's leg and foot. Then,such a lining (12) is inserted on the core (1) of the mold (S), beforethe fabric upper (10) is inserted on the core (1), as e shown in FIG. 6.

Referring to FIG. 6A, it must be noted that the lining (12) is providedon a bottom with one or more holes for a corresponding number ofdiffusers (D) mounted on the bottom (1 p) of the core (1); Each hole ofthe lining (12) is crossed by a diffuser (D).

In view of the above, the lining (12) perfectly adheres to the bottom (1p) of the core (1) and the diffusers (D) are disposed in externalposition on the lining (12).

Then the fabric upper (10) is inserted onto the core (1) in externalposition with respect to the lining (12). Therefore, in such a case, theintermediate space (4 a) adapted to receive the plastic material influid state is created between the upper (10) and the lining (12).

Moreover, the fabric upper (10) is provided on the bottom (10 p) with acontinuous surface that prevents the diffusers (D) from ending outsideof it.

It can be otherwise said that the diffusers (D) are disposed between theinternal side of the lining (12) and the internal side of the fabricupper (10), specifically in the intermediate space (4 a).

For this reason, also in this situation, the pointed head (31) of eachinjection nozzle (30) provided in the first lid (3) penetrates thefabric upper (10) before penetrating the central chamber (100 c) of acorresponding diffuser (D).

When the injection of plastic material in fluid state is activated, thematerial delivered by the pointed head (31) of the nozzle (30)penetrates the central chamber (100 c) of a diffuser (D) and is ejectedfrom the diffuser (D) through the radial slots (100 d).

In such a condition, the plastic material in fluid state that is ejectedfrom the radial slots (100 d) of the diffuser (D) is received in theintermediate space (4 a) provided between the upper (10) and the lining(12), in order to generate the desired waterproofing layer (10 a)between the upper (10) and the lining (12) after consolidation and inorder to irreversibly join the upper (10) and the lining (12), as shownin FIG. 7.

Although according to the process of the invention the diffusers (D) ofthe plastic material in fluid state are mounted in the bottom (1 p) ofthe core (1), it is understood that the process of the invention can beimplemented also without the diffusers (D). In fact, the pointed head(31) of the nozzle (30) coming out of the hole of the first lid (30)simply needs to perforate the fabric upper (10) before starting toinject plastic material in fluid state. In this way the plastic materialpenetrates the intermediate space (4 a) provided between the core (1)and the internal side of the fabric upper (10), thus creating thenecessary internal coating layer (10 a).

If the fabric upper (10) is to be coated with the lining (12)—andconsequently both the fabric upper (10) and the lining (12) are insertedon the core (1)—the pointed head (31) of the injection nozzle (30) onlyperforates the fabric upper (10) and not the internal lining (12). Inview of the above, the injection material in fluid state penetrates andconsolidates in the intermediate space (4 a) formed between the upper(10) and the lining (12).

Even if the detailed description is referred specifically to a boot, themethod according to the invention is extended to any type of shoeprovided with upper. It is evident that, if the shoe is not a boot, theshoe comprises a upper that does not provided with the tubular portionsurrounding the leg and therefore the mould comprises a die (2) shorterthe one showed in the Figures, in order to surround only the foot of thecore (1).

1. Manufacturing process of a shoe with fabric upper comprising thefollowing steps: a) inserting an upper onto a core of a mold; said corehaving the shape of a foot and said upper being in fabric, having theshape of sock, and having an internal surface facing toward the core; b)fixing the core with the upper inside the mold adapted to surround thecore, so as to generate a gap between the core and the mold; c)injecting fluid plastic material inside the gap of the mold through oneor more injection nozzles in order to obtain a coating layer of theupper, wherein before the injection step (c), a piercing step of theupper is performed, by means of a pointed head of said one or moreinjection nozzles for injecting fluid plastic material in anintermediate space between the upper and the core, in order to cover theinternal surface of the upper.
 2. The process of claim 1, wherein saidcore has a bottom, said upper has a bottom and said fixing stepcomprises: fixing of a lateral wall of the core inside a die in order togenerate a lateral gap between the core and the die, closing of the diedwith a first lid in order to generate a lower gap between the first lidand the bottom of the core, said lower gap communicating with saidlateral gap, wherein said one or more injection nozzles are associatedwith said first lid, so that the pointed head of said one or moreinjection nozzles pierced the bottom of the upper.
 3. The process ofclaim 1, which comprises the following step after the injecting step(c): d) removal of the first lid and mounting of a second lid providedwith one or more injection nozzles of the second lid adapted to deliverthe fluid molding material inside a cavity of the second lid to mold asole and incorporate the sole under the bottom of the upper.
 4. Theprocess of claim 1, wherein a lining is inserted onto the core beforethe inserting step (a), in such manner that the fluid plastic materialinjected by said one or more injection nozzles penetrates anintermediate space provided between the lining and the upper.
 5. Theprocess of claim 4, wherein the pointed head of each of said one or moreinjection nozzles injects the fluid plastic material inside a diffuserfixed to the core and adapted to be disposed in the intermediate spacebetween said upper and the core.
 6. The process of claim 5, wherein eachdiffuser is disposed in intermediate position between said upper andsaid lining.
 7. The process of claim 5, wherein each diffuser is fixedto the core by means of a fixing pin protruding by a cylindrical plateof the diffuser, each nozzle is coupled to a cylindrical chamberobtained into the plate of the diffuser, and plastic material deliveredby the nozzle enter into the cylindrical chamber of the plate of thediffuser and radially spreads toward the exterior, through radial slotsobtained in a lateral wall of the plate of the diffuser.
 8. The processof claim 1, wherein said injection nozzles are incorporated in the firstlid of the mold.
 9. The process of claim 1, wherein said plasticmaterial used for the coating layer of the fabric upper is PVC. 10.Molding assembly for manufacturing of a shoe with fabric uppercomprising: a core having the shape of a foot and said core beingsuitable to receive an upper being in fabric, having the shape of sock,and having an internal surface facing toward the core; a mold disposedon the core, so that to generate a gap between the core and the mold,surrounding the core; one or more injection nozzles crossing the moldfor injecting plastic material into the gap of the mold, to cover theupper, wherein said one or more injection nozzles comprises a pointedhead suitable for piercing the upper for injecting fluid plasticmaterial in an intermediate space between the upper and the core, inorder to cover the internal surface of the upper.
 11. Molding assemblyof claim 10, comprising at least one diffuser fixed to said core andadapted to coupling with said pointed head of said one or more nozzle,in order to spread the plastic material in said intermediate spacebetween the core and the upper.
 12. Molding assembly of claim 11,wherein said diffuser comprises a cylindrical chamber coupling with saidpointed head of the nozzle and a plurality of radial slot to radiallyspread the plastic material injected into the cylindrical chamber of thediffuser.
 13. Molding assembly of claim 10, wherein the core has abottom, the upper has a bottom disposed under the upper of the core andthe mould comprises: a die suitable for laterally surrounding said corein order to generate a lateral gap between the core and the die, and afirst lid suitable for closing the die at the height of the bottom ofthe core, in order to generate a lower gap between the bottom of thecore and the first lid, said lower gap communicating with said lateralgap, wherein said nozzle crosses the first lid and said pointed head ofthe nozzle pierces the bottom of the upper for injecting plasticmaterial in the intermediate space between the core and the upper.